Conventionally, for plastic oil and fat foods such as margarine and shortening, hardened oil and liquid oil, which is in a liquid form at normal temperature, are used in combination. In recent years, it has been reported that trans fatty acids contained in hardened oil cause a rise in LDL and cholesterol quantities, and also increase the risk of carcinogenesis. Thus, plastic oil and fat compositions with reduced or no trans fatty acid are required.
As an oil and fat with reduced or no trans fatty acid, palm oil, extremely hardened oils, liquid oils, and others are generally known. However, when using some of these oils and fats in combination for making a plastic oil and fat food, the resultant food does not become satisfactory in quality because of a shortage in plasticity, the generation of coarse crystals therein, a poor melt-in-the-mouth property, etc.
In order to obtain a plastic oil and fat composition that hardly contains any trans isomer and is good in quality and others, using a natural solid oil and fat and others as raw materials, JP2007-174988A discloses a plastic oil and fat composition made by mixing the followings: 15 to 80% by weight of non-selective interesterified oils containing 15 to 40% by weight of a saturated aliphatic acid having 12 carbon atoms and 30 to 80% by weight of a saturated aliphatic acid having 16 to 18 carbon atoms; and 85 to 20% by weight of an oil and fat in which PPO+POP is from 13 to 55% by weight and PPO/POP>1. In this plastic oil and fat composition, laurin-based oil and fat is used so that the oil and fat may be hydrolyzed to generate soapy smell. Moreover, the composition has a problem against the feeling of melt-in-the-mouth, spreadability, and other qualities, as will be described in Comparative Example 6 in the present specification.
JP2007-177100A discloses a plastic oil and fat composition in which the content of PPP is from 4 to 18% by weight, PPO+POP is from 15 to 55% by weight, PPO/POP>1, and (PPO+POP)/PPP>1.8 in order to obtain a plastic oil and fat food with good operability in production, storability etc., using hardened oil and fractionized oil with reduced trans isomer. In the production of this plastic oil and fat composition, no lauric acid is used. However, the resultant plastic oil and fat food has a problem against the feeling of melt-in-the-mouth, spreadability, and other qualities, as will be described in Comparative Example 5 in the present specification.
JP2009-291168A discloses that the following oil and fat composition is excellent, after long preservation, in plasticity, operability when made into bread or sweets, melt-in-the-mouth property, and flavor: an oil and fat composition for margarine containing two interesterified oils and fats with different iodine values which contain at least one of PPP, PPO and POP in a specific content. However, for this composition, the iodine values must be controlled in predetermined values, and further the production method includes an extremely hardening step so that the operation becomes complicated. Thus, the composition is not very practical. Additionally, the composition has problems about filling operability, hardness and shape-keepability, as will be described in Comparative Example 4 in the present description.
As described above, the plastic oil and fat composition as a base oil and fat (of the food) is unsatisfactory, since plastic oil and fat food made by use of a conventional plastic oil and fat composition is insufficient in filling operability and qualities.